For the above reasons, reliably and securely handling an otoscope of the art is currently subject to only well trained physicians and not amenable to the larger community of practitioners. A study recently published in the US as a result of a survey has shown that even physicians often fail to (correctly) determine the status of e.g. the subject's eardrum or fail to correctly interpret the image provided by the otoscope (i.e. correct and meaningful object recognition). Such failures result in misinterpretation of the status of the inner ear canal or the eardrum. As a consequence, e.g. over-medication with antibiotics for treating supposed inflammations of the eardrum occurs, because physicians tend to err on the side of caution, or meaningless image interpretation occurs.
Notably, there also exist other otoscopic devices, as e.g. video otoscopes, allowing a skilled expert to capture images of the subject's eardrum and the ear canal. Such video otoscopes comprise a bundle of light guides extending from the distal end of the head portion to a CCD-chip located remote from the distal end. The achievable resolution of the images depends on the number of light guides. In order to obtain images having a satisfying resolution, a significant number of individual light guides must be provided rendering devices by far too expensive for routine care. Moreover, all of the known video otoscopes having the CCD-chip located remote from the distal end of the head portion require superior handling skills by the physician. For the above reasons, they are not configured and suitable for domestic use by a larger community of practitioners, nor use by laypersons.
All otoscopes currently on the market—including video otoscopes—generally are based on the following fundamental design: a relatively thin open funnel. Length, angle, field of vision and size of the funnels are essentially similar for all marketed otoscopes. As a result of these common characteristics, ease of use (due to safety issues) is limited for such devices. Methods for reliable detection of objects in the ear canal, including the eardrum, are remarkably intricate with such known otoscopes.
Consequently, until today otoscopy has almost been exclusively applied by medical doctors. And even among medical doctors, only a minor percentage is sufficiently trained to carry out otoscopy in a reliable and appropriate way. However, since otitis media is the most frequent disease causing high fever in young children, and to exclude otitis media, especially OME, is a major reason for seeing a pediatrician, there is an urgent need for a parental check of the ear. Parents may also benefit from an otoscope that can be securely used by laypersons at home in order to check whether an ear canal of their child is blocked by massive earwax and/or foreign objects.
Prior art document U.S. Pat. No. 5,910,130 A describes an otoscope with a miniature video camera or a solid-state imager, e.g. a CCD or CMOS. A light source can be provided in the form of a continuous ring of light emitting fibres. The head portion of the otoscope has to be introduced far into a straightened ear canal in order to observe the eardrum.
Prior art document EP 2 289 391 A1 describes an otoscope with a head portion and a fastening ring for reversibly mounting the head portion to a display portion.
It is therefore an object of the present invention to provide an otoscope that allows for domestic application by laypersons and medical doctors without extensive otoscopy training and without any—or at least with a significantly reduced—risk of causing injuries to the patient. In particular, it is an object of the present invention to provide an otoscope that allows for domestic application by laypersons without the need of cleaning, especially sterilizing, the otoscope, i.e. with minimized danger of infections, especially without restricting the ability of identifying objects within the ear canal. The object of the present invention can also be describes as to provide a method allowing for reliably identifying objects within the ear canal, any danger of infections being minimized.
This object is achieved according to the present invention by an otoscope exhibiting the features of claim 1 or by a probe cover exhibiting the features of the respective independent claim or by a method of identifying objects in a subject's ear, the method exhibiting the features of the respective independent claim. Preferred embodiments represent the subject-matter of the respective dependent claims.
In particular, this object is achieved by an otoscope of the generic type as described above, wherein the otoscope further comprises an electronic imaging unit positioned at the distal end of the head portion, especially at a distal tip of the head portion, wherein the otoscope further comprises a probe cover moving mechanism configured to move at least a portion of an at least partially transparent probe cover adapted to be put over the head portion, especially configured to move the probe cover with respect to at least one optical axis of the electronic imaging unit.
With an otoscope comprising a probe cover moving mechanism, artifacts, such as earwax particles, adhering to the probe cover and obstructing the view of the electronic imaging unit or camera onto the eardrum can be moved away by the probe cover moving mechanism. In particular for hygienic reasons, in most of the use cases, the otoscope is coupled with an at least partially transparent probe cover adapted to be put over the head portion. The probe cover may be made from a plastic material, preferably from a transparent plastic material. Such a probe cover may be designed as a single-use product that can be produced in larger numbers with low costs. The probe cover shall be transparent, at least at the locations where it covers an observation point, especially an eccentric observation point, i.e. where it intersects an optical axis of the electronic imaging unit, so as to allow the electronic imaging unit to have a clear view onto the eardrum. The probe cover also inhibits contamination of the head portion of the otoscope comprising the electronic imaging unit, in particular when introducing the head portion into the patient's ear canal.
The probe cover moving mechanism can be provided e.g. in the form of a latch mechanism or an automatized mechanism which is driven by a motor. The probe cover moving mechanism allows for controlled, predefined relative displacement, especially in an axial direction, i.e. parallel to the longitudinal axis of the head portion. Preferably, the probe cover moving mechanism is configured for interacting with a proximal portion of the probe cover and is configured for an axial motion or displacement of the probe cover or a portion of the probe cover, be it in a distal and/or in a proximal direction. As an alternative or in addition, the probe cover moving mechanism can be configured for rotating the probe cover.
According to one embodiment, the moving mechanism is configured to move the probe cover in a direction which is at least approximately parallel to the longitudinal axis, especially by exerting a pulling force on the probe cover. Such a moving mechanism may ensure homogeneous tension within the probe cover and may homogeneously press the probe cover onto the outer surface of the head portion, especially in conjunction with a conical shape of the head portion. Also, such a moving mechanism can conveniently interfere with the probe cover at a proximal end of the probe cover.
Preferably, in addition, the moving mechanism is configured to move at least a portion of a reservoir of the probe cover in a direction which is at least approximately orthogonal to the longitudinal axis. Such a moving mechanism may ensure that ear wax or any other particles obstructing the view can be displaced out of the line of sight effectively, especially in conjunction with radially offset optical axes.
According to one embodiment, the moving mechanism is configured to unfold a/the reservoir of the probe cover by stretching a distal portion of the probe cover. Such a moving mechanism may ensure that ear wax or any other particles obstructing the view can be displaced away from the distal tip of the head portion effectively.
According to one embodiment, the electronic imaging unit exhibits at least one optical axis which is positioned radially offset from the longitudinal axis, the moving mechanism being configured to move the probe cover with respect to the at least one radially offset optical axis. Providing a small electronic imaging unit (or an electronic imaging unit with optical components having small radial dimensions) at the distal end of the head portion exhibiting at least one optical axis which is radially offset allows to “see” the patient's eardrum without the need to deform the patient's ear canal, or at least without having to deform the ear canal to such an extent as with the above described conventional otoscope. The reason for this is that there is no need for the “viewing direction” of the electronic imaging unit to correspond to the longitudinal axis of the head portion of the otoscope. Rather, the radial offset can ensure that there is a line of sight onto the eardrum even if the ear canal is not straightened, allowing the device to “look around the corner”.
In particular, in many cases, the ear canal of the outer ear is not straight-lined, but exhibits at least one curvature, especially at a transition area or transition point between soft connective tissue and hard bone confining the ear canal. The “corner” is provided by this curvature. In particular, virtually almost always, the ear canal has an S-shaped (sigmoid) form with a first curvature and a second curvature, the second curvature being closer to the eardrum than the first curvature. Particularly, the second curvature of the ear canal obstructs any optical line of sight or visual communication of an otoscope which is not introduced as far as at least some millimeters within the bony part of the ear canal. The “corner” can be defined as the second curvature of the ear canal. In particular, in a distal direction, the second curvature leads to the bony part of the ear canal. A transition point or area between soft connective tissue and hard bone is arranged at this second curvature, at least most often. The second curvature leads into the section of the ear canal which is exclusively confined by hard bone. Preferably, the transition area can be defined as an area of about a few millimeters distal to (behind) and about a few millimeters proximal to (in front of) a curvature, especially 0 mm to 5 mm or 1 mm to 3 mm.
In particular, the probe cover moving mechanism may ensure that an optical axis of the electronic imaging unit can be arranged with a relatively large radial offset, especially without evoking the problem of any earwax particles obstructing visibility or with reduced probability of such earwax particles. Earwax particles are often arranged at an inner surface surrounding the ear canal. Thus, for an optical axis being arranged with a high radial offset, i.e. close to an inner lateral surface of the ear canal, there may be an increased likelihood of earwax particles adhering to the probe cover at a section covering the optical axis, thereby obstructing the view onto the eardrum. In other words: There may be an increased likelihood of earwax particles obstructing the view from an optical axis which is radially offset than from an optical axis which is arranged at least approximately centrically. The probe cover moving mechanism can ensure that the view onto the eardrum is not obstructed, even in case the optical axis is arranged with a maximum radial offset close to an inner lateral surface of the ear canal. Thus, the present invention is based on the finding that by providing a probe cover moving mechanism, observation of the eardrum from an eccentric observation point with a relatively large radial offset can be made more practicable and more reliable. A probe cover moving mechanism can ensure that the concept of “looking around the corner” is feasible and can be realized in a convenient way, even in case the ear canal is obstructed by several objects.
In particular, for displacing any particles or ear wax out of the line of sight, a relative motion or displacement of the probe cover induced by the moving mechanism is most effective in case the optical axis is positioned radially offset, especially with a maximum radial offset. The present invention is based on the finding that in most cases, it may be most favorable displacing the entire probe cover, apart from a central distal point at the distal tip of the probe cover. In other words: The whole probe cover can e.g. be pulled backwards in a proximal direction, except for a central distal point at the distal tip of the probe cover. At this distal point, preferably, a probe cover reservoir is provided. Thus, relative motion between the probe cover and the head portion may be minimum at the distal point, but maximum at any point of the distal tip which is positioned radially offset.
An otoscope exhibiting a probe cover moving mechanism in conjunction with a radially offset electronic imaging unit may be used by laypersons, without extensive otoscopy training and with a significantly reduced risk of causing injuries, especially with a significantly reduced risk of irritation of the patient's tissue, e.g. the tissue within the hard bone section of the ear canal. Such an otoscope allows for observing the eardrum substantially irrespective of the relative position of a head portion within the ear canal, especially irrespective of any specific insertion depth into the bony part of the ear canal, i.e. the section confined by hard bone. As the otoscope is arranged for “looking around the corner or curvature”, the layperson does not have to introduce the head portion as far as a section of the ear canal which is confined by hard bone.
While in traditional otoscopy, the physician has to introduce the otoscope at least as far as some millimeters within the bony part of the ear canal, i.e. considerably further inwards than the second curvature, an otoscope according to the present invention can be positioned adjacent to the second curvature. In traditional otoscopy, the otoscope is necessarily introduced far into the bony part of the ear canal, especially in order to provide a kind of support or rest or anchoring point at the distal tip of the otoscope. Once the distal tip of the otoscope is supported within the bony part, the physician can apply a leverage on the handle portion of the otoscope, in order to straighten the ear canal and in order to ensure an optical line of sight onto the eardrum. But, this kind of “alignment” of the otoscope or this kind of straightening out the ear canal is painful. In contrast, the otoscope according to the invention does not require such an “alignment” or straightening.
Preferably, the radial offset is at least factor 0.25 of the radial dimension of the distal end, preferably at least factor 0.3, more preferable at least factor 0.35. Such a relatively large radial offset can ensure positioning the optical axis in a favorable eccentric observation point within the ear canal, even in case the distal tip in introduced only as deep as a transition point between soft connective tissue and hard bone. According to one embodiment, the at least one optical axis is arranged as close as possible to an inner lateral surface of the distal end. Thereby, the radial offset can be maximized.
Preferably, the electronic imaging unit or at least an optical component thereof, e.g. a lens, is positioned at the most distal part of the head portion. In particular, the electronic imaging unit can be in contact with a front side or front face of the head portion, or the electronic imaging unit can provide a front side or front face of the head portion. This enables positioning the electronic imaging unit most distal within the ear canal without the need of introducing the head portion deep into the ear canal.
The otoscope according to the present invention may comprise further features that are provided, for example, by modern digital photo cameras. For example, the otoscope may comprise visual output means, such as a display, and/or acoustic output means, such as a loudspeaker, and/or a storage card slot for inserting a storage card to store the acquired images, and/or a cable connection port, such as an USB-port, and/or a wireless connection, such as Bluetooth®, WIFI®, and/or an energy supply, such as a battery.
Preferably, an “optical axis of the electronic imaging unit” is an axis which extends from a most distal point of the electronic imaging unit in a distal direction, especially towards the eardrum, wherein its orientation is not modified any more by any optical components. The “optical axis of the electronic imaging unit” of an electronic imaging unit preferably is the optical axis with the largest radial offset.
The electronic imaging unit may comprise a video camera defining an optical axis, preferable a wide angle color video camera. The term “wide angle” in this context refers to angels of at least 80°, preferably of at least 110°, e.g. 120°. Such wide angle cameras allow detection of the patient's eardrum, even if the optical axis of the camera is not directly centered to the eardrum and even if the eardrum is relatively remote from the camera, compared to the distance between the eardrum and the tip end of a conventional otoscope head during application. Using a color video camera is advantageous, allowing determination of the color of the eardrum and/or of the inner portion of the ear canal. Thus, inflammations can be detected by the degree of reddishness.
The electronic imaging unit may comprise a miniature camera, in particular a wafer-level camera of a substantially flat configuration, having dimensions of less than 3 mm×3 mm, preferably less than 2 mm×2 mm, especially 1.2 mm×1.2 mm, even more preferable of about 1 mm×1 mm or even less than 1 mm×1 mm. Wafer-level cameras refer to a relatively new technology. They can be produced small in size with only about 3 microns per pixel. Therefore, wafer-level imaging technology allows obtaining images of “sufficient” resolution of the eardrum, e.g. images of 250 pixels×250 pixels, with a footprint of the camera including lens of only about 1 mm×1 mm or even smaller.
The term “miniature camera” refers to cameras having minimum dimensions with respect to the required method of capturing images, preferably lateral or radial dimensions in the range of 0.5 mm to 2.5 mm, more preferably in the range of 0.5 mm to 1.5 mm, or 1 mm. A “miniature camera” may exhibit a diameter in the range of e.g. 0.5 mm to 1.5 mm. The dimensions of the camera in an axial direction (parallel to the longitudinal axis) is circumstantial, i.e. only of minor importance. Radial dimensions of less than 2 mm×2 mm, even more preferable of about 1 mm×1 mm provide the advantage that an optical axis of the electronic imaging unit or camera can be arranged very close to an inner or outer lateral surface of the head portion, thereby enabling the otoscope to “look around the corner” with a relatively big angle, e.g. an angle in the range of 10° to 60°, preferably in the range of 15° to 40°, more preferable in the range of 20° to 30°.
A camera based on wafer technology provides a good compromise between light sensitivity and space requirements. The light sensitivity depends on the dimensions of an aperture or lens of the camera. The bigger the aperture, the higher the light sensitivity.
One optical axis of the electronic imaging unit may be positioned substantially centrically with respect to the longitudinal axis of the head portion. If one optical axis of the electronic imaging unit is positioned on the longitudinal axis of the head portion, a substantially flat optical component of the electronic imaging unit is preferable inclined or inclinable with respect of the longitudinal axis of the head portion, so that the one optical axis (or a “viewing direction”) of the electronic imaging unit is angled with respect to the longitudinal axis (tilted against the longitudinal axis) of the head portion, allowing the otoscope to “look around the corner” even from a central observation point.
The electronic imaging unit may comprise at least one optical axis, e.g. provided by a camera, preferably at least three or four optical axes provided by at least three or four wafer-level cameras which is/are positioned radially offset from the longitudinal axis of the head portion. Such a configuration also allows obtaining a free view onto the eardrum without having to introduce the electronic imaging unit as deeply as it would be necessary if the electronic imaging unit only had one optical axis placed just centrally on the longitudinal axis of the head portion. The offset may be at least 1 mm, preferably at least 2 mm, more preferably at least 2.5 mm from the longitudinal axis. Preferably, the maximum radial offset is within the limits of the outer diameter of a distal tip of the head portion.
The head portion is preferably shaped such and exhibits radial dimensions such that its distal end comprising the electronic imaging unit can be introduced only as deep into the ear canal as not to touch the eardrum, especially only as deep as not to touch the hard bone, or at most only as far as some millimeters within the section confined by hard bone. The ear canal of the patient's outer ear is limited by the eardrum. Notably, the ear canal of the patient's outer ear comprises an outer part which refers to a portion of the patient's outer ear (i.e. the patient's external auditory canal) that is surrounded by soft connective tissue and that usually comprises hair and earwax. The outer part comprises approximately the outer half of the ear canal of the patient's outer ear. Furthermore, the ear canal of the patient's outer ear also comprises an inner part which refers to a portion of the patient's outer ear (i.e. the patient's external auditory canal) that is surrounded by hard skull bone and that is usually free from any hair and earwax. This portion extends from the proximal end the outer part of the ear canal of the patient's outer ear to the eardrum. The inner part of the ear canal is very sensitive to pain in case of injury by mechanical friction. Injuring the inner part of the ear canal even bears the risk of cardiovascular complications through vagal overstimulation.
Preferably, the head portion is shaped in such a way that its distal end comprising the electronic imaging unit can be introduced only in an area of the ear canal which is confined by soft connective tissue, but not in an area of the ear canal which is confined by hard bone. On the one hand, such a shape can ensure that the distal end does not touch the eardrum, even if the otoscope is applied by laypersons. On the other hand, the otoscope can be applied by layperson without the need of correcting the position of the head portion within the ear canal. Rather, the head portion only has to be positioned “somehow” within the ear canal, which even can be made by the same person. In other words: There is no need of any assistance at all, which is favorable e.g. for an application by older people living on one's own. The otoscope according to the present invention even can enable an application by the layperson. In particular, the otoscope is arranged to “look around the corner” such that it is sufficient to introduce the head portion only in an area of the ear canal which is confined by soft connective tissue.
Introducing the head portion only in an area of the ear canal which is confined by soft connective tissue can ensure that there is reduced friction between an inner lateral surface of the ear canal and the probe cover during displacement of the probe cover. Introducing the head portion not as deep as in an area of the ear canal which is confined by hard bone can ensure that any relative motion between the probe cover and the inner lateral surface of the ear canal does not irritate any tissue which is pain sensitive.
Preferably, a tip portion of the distal end can be introduced into the ear canal of the patient's outer ear no further than to a distance from the eardrum of at least a few millimeters, preferably of at least 3 mm, more preferable of at least 10 mm, further preferred of at least 15 mm.
As already mentioned above, the tapering head portion of the otoscope according to the present invention can be shaped with a blunt, rounded tip end, as compared to a conventionally known otoscope, thereby reducing the risk of introducing injury or discomfort to the patient. Thus, the device can be securely handled by laypersons. The otoscope according to the present invention, nevertheless, allows detecting the eardrum, since the electronic imaging unit is provided at the distal end of the head portion, and any objects adhering the probe cover and obstructing vision into the ear canal, especially onto the eardrum, can be displaced by displacing the probe cover.
Preferably, the distal end of the head portion is provided with a round and smooth shape. Moreover, the distal end may be made from a relatively soft material, such as silicone, or it may comprise an outer surface made of such a soft material. Furthermore, the longitudinal force upon introduction into the ear canal can be limited by a telescoping mechanism or the use of an elastic element.
The functional concept of a conventional otoscope as described above, however, requires the tip end of the head portion to be relatively small and acute (sharp), usually having a diameter of only about 3 mm. It is noted that the diameter of the inner part of the outer ear canal of an adult is about 4 mm. Therefore, if the user (untrained) does not pay attention, the tip portion might be introduced deeply into the inner part of the outer ear canal causing serious injuries to the patient. To substantially avoid this risk, the head portion of the otoscope according to the present invention (also having a tapered shape) preferably exhibits a diameter of at least 4 mm, preferably of more than 5 mm, more preferably of more than 6 mm, at a position along the longitudinal axis of the head portion of no more than 4 mm from a distal end point of the head portion. Thus, it is geometrically excluded to introduce the distal end of the head portion too far into the subject's ear canal. Different geometries of tapers may preferably be used according to the age group of the subject. For children, for example, the head portion of the otoscope adapted to carry out the method according to the present invention may exhibit a diameter of about 5 mm at a position along the longitudinal axis of the head portion of no more than 4 mm away from a distal end point of the head portion. For example, the head portion can be provided with a first specific shape for children at the age of 0 to 2 years and with a second specific shape for any patient at the age of more than 2 years. But, it is not necessarily required to use different geometries of tapers according to the age group of the subject. Rather, the inventive shape of the head portion can be used by all age groups, as it is not required to introduce the head portion far into the subject's ear canal. Thus, the inventive shape of the head portion can provide a universal speculum.
Preferably, the distal tip of the head portion exhibits an diameter, especially an outer diameter, of at least 4.0 mm, at least 4.7 mm, preferably of more than 4.8 mm, more preferably about 4.9 mm. A head portion with a distal tip having a diameter, especially an outer diameter, of about 4.7 mm, 4.8 mm or 4.9 mm is not adequate or appropriate for classical otoscopy, especially for observing the eardrum of a child. Such a relatively large tip could not be inserted into the ear canal as far as considerably within the bony part, especially in childrens' ears. The head portion would be blocked at a position too far away from the eardrum, at least within ears of children. It would not be possible to observe the eardrum. There would not be any line of sight onto the eardrum. It would not be possible to align the otoscope within the ear canal such that the eardrum is visible. The head portion would not be introduced far enough for aligning the entire ear canal.
In contrast, according to the present invention, a distal tip with a diameter of about 4.7 mm, 4.8 mm or 4.9 mm can ensure that the distal tip cannot be inserted further into the ear canal than a position within the part of the ear canal which corresponds to a transition area between soft connective tissue and hard bone surrounding the ear canal. In particular, at most, the distal tip of the head portion is docked to or coupled to a proximal end of the bony part. At most, the distal tip of the head portion is positioned at the outer end of the bony part of the ear canal, but not further inwards. In other words: The head portion of the otoscope is preferably shaped in such a way that its distal end comprising the electronic imaging unit or optical component (e.g. camera) can be introduced only as deep into the ear canal as a transition area between soft connective tissue and hard bone confining the ear canal. Preferably, a diameter of an inner lateral surface of the distal end is in the range between at least 4.2 mm, preferably more than 4.4 mm, more preferably about at least 4.5 mm or 4.6 mm, in order to allow maximum radial offset.
The head portion may exhibit a conical portion with an opening angle α in the range of 3° to 10°, preferably 4° to 8°, especially 5° or 6°. Such opening angles can ensure that, in case the layperson tries to introduce the head portion as far as a section of the ear canal which is confined by hard bone, further insertion of the head portion is blocked within the ear canal well before reaching the eardrum.
Preferably, the head portion exhibits a distal tip with a first diameter (d1) in the range of 4 mm to 6 mm, preferably 4.5 mm to 5.3 mm, further preferred 4.7 mm to 5.1 mm, especially 4.9 mm. At a longitudinal position defined by a specific length, the head portion preferably exhibits a second diameter (d2) in the range of 7.5 mm to 9.5 mm, preferably 8 mm to 9 mm, further preferred 8.3 mm to 8.8 mm especially 8.5 mm. Preferably, the ratio of these diameters (d1:d2) is in the range of 0.57 to 0.65, especially about 0.58 or about 0.63. Such a shape can ensure that the head portion is blocked well before reaching the eardrum. Preferably, the specific length is in the range of 18 mm to 22 mm, more preferable 19 mm to 21 mm, especially 20 mm. These diameters or ratios can ensure that the head portion, especially the distal end, exhibits geometrical dimensions ensuring that the head portion can be introduced only in the area of soft connective tissue confining an outer ear canal of the patient's outer ear, but not in the area of hard bone confining the outer ear canal. Such a shape can ensure that the otoscope can be applied by laypersons without the risk of irritations of the tissue.
Preferably, the probe cover exhibits a shape or an inner contour which geometrically corresponds with the shape of the head portion. In particular, the probe cover exhibits the same shape as the head portion, as describes above. A wall thickness of the probe cover preferably is in the range of 0.02 mm to 0.05 mm. Therefore, an outer shape or contour of the probe cover can be characterized by the measurements stated with respect to the head portion, adding 0.04 to 0.1 mm in diameter.
The head portion and/or the handle portion may exhibit fixation means for fixing a probe cover at the otoscope. Thereby, a probe cover can be fixed at the head portion or handle portion such that relative motion can be prevented. Such fixations means can prevent premature unfolding of the probe cover, as relative motion between the head portion and a probe cover is only enabled at a time when the distal tip is introduced far enough. The risk of ear wax obstructing visual communication can be minimized.
Further, the otoscope may comprise at least one light source positioned at the distal end, especially at the distal tip, the moving mechanism being configured to move the probe cover with respect to the at least one light source. Such a moving mechanism allows for displacing any objects, e.g. ear wax, away from an illumination point, especially a favorable eccentric illumination point. Preferably the at least one light source is positioned radially offset from the longitudinal axis.
The term “light source” is understood to apply to any source emitting photons. A light source positioned at the distal end or tip ensures illumination of the ear canal, even in case the distal tip is only introduced as deep as a transition area between the two types of tissue. Distal eccentric light sources facilitate realization of the concept of “looking around the corner”.
Since geometrical restrictions limit the space at the distal end of the head portion, the light source is preferably formed by the distal end of a light guide. For example, the light guide may exhibit a diameter of less than 1 mm, preferably of less than 0.5 mm, more preferably of about 0.2 mm. The light guide may be connected to an LED located remote from the distal end of the head portion. The light guide may be e.g. a nylon light guide, preferably having a diameter of only about 0.2 mm to 1 mm. Alternatively, a light source may be formed e.g. by a small light emitting diode (LED) that is placed directly at the distal end of the head portion. The LED can ensure illumination with low energy consumption and minimum generation of heat.
The light guide can be made of polymethyl methacrylate (PMMA) or polyamide, especially polyamide 6.6. PMMA provides the advantage of good optical characteristics. Polyamide 6.6 provides the advantage of high flexibility.
The light guide may allow placement of the light source at a distance from the distal end with less spatial constrains and space for means (e.g. a printed circuit board) for effective heat dissipation. Such an arrangement facilitates realization of the concept of “looking around the corner”, especially as the light guides may be arranged with a maximum radial offset without any risk of thermally damaging tissue. Effective heat dissipation reduces the impact of the otoscope on the tissue confining the ear canal, avoiding thermal irritation of the tissue.
It is advantageous, if the otoscope comprises a plurality of light sources at the distal end of the head portion, preferably with each light source being separately controllable. Thereby, the ear canal can be illuminated from a favorable eccentric illumination point, reducing e.g. shadowing. Also, by illuminating objects in the patient's ear canal from different positions, e.g. by sequentially switching on and off the individual light sources, it may also be envisaged to distinguish different objects in the ear, without necessarily having to displace the electronic imaging unit by a motion mechanism within the ear canal. An object relatively far away from the electronic imaging unit, such as the eardrum, will change its appearance only slightly when being illuminated from different positions at the distal end of the head portion. However, artifacts that are relatively close to the electronic imaging unit (such as hair and earwax) will change their appearance (position) drastically. The otoscope therefore preferably comprises means, in particular a logic unit, such as a microprocessor, configured to distinguish different objects in the patient's ear based on images taken with the objects being illuminated from different positions.
Preferably, a logic unit is coupled with at least two of the light sources and is arranged for individually switching on and off the light sources and/or for individually varying the light intensity. Additionally or alternatively, the at least one light source may be controllable in view of the color, so that it is possible to change the color of the light emitted by the light source. For example red color may be preferred to recognize an inflamed eardrum, wherein green color may be preferred to recognize earwax.
The otoscope may comprises a logic unit which is coupled with at least two of the light sources and is arranged for individually switching on and off the light sources and/or for individually varying the light intensity. Individually switching on and off enables stereoscopic viewing, especially depth analysis along the optical axes due to changes in reflected light patterns. Also, segmented lighting of the ear canal can be carried out. For example, three light sources each illuminate a specific portion of the ear canal. Feedback regulation of each of the light sources allows for homogeneous illumination of the ear canal, especially based on different illumination levels. Preferably, a logic unit is coupled to each of the light sources, the logic unit allowing for feedback regulation and/or adjustment of illumination levels.
Like the electronic imaging unit, the at least one light source is preferably positioned radially offset from the longitudinal axis of the head portion. Such a configuration allows illumination of the eardrum without the need to introduce the light source as deeply into the ear canal as it would be necessary, if the light source were placed centrally on the longitudinal axis of the head portion. The offset may be at least 1 mm, preferably at least 1.5 mm, more preferably at least 2 mm from the longitudinal axis. Preferably, the offset is maximum with respect to the confines of the outer diameter of the head portion. According to one embodiment, the offset is in the same range as a radial offset of the at least one optical axis. According to one embodiment, the radial offset of the at least one light source is as large as a radial offset of a camera of the electronic imaging unit. Such an arrangement is favorable in order to observe the entire eardrum or in order to reduce shadowing.
According to one embodiment, the moving mechanism is configured for automatically initiating relative displacement of the probe cover based on mechanical reaction forces exerted by the probe cover on the moving mechanism. Such a moving mechanism enables adequate use by laypersons, even in case a layperson is not aware of appropriate handling of the otoscope. In particular, with such a mechanism, the probe cover can be displaced at a time when the head portion is blocked in an end position within the ear canal, especially at a transition area between soft connective tissue and hard bone.
According to one embodiment, the moving mechanism comprises an adapter which is arranged to axially position the probe cover in at least one specific axial position relative to the head portion. A predefined axial position allows for providing a probe cover reservoir which is not unfolded unintentionally during insertion of the head portion. The adapter preferably exhibits fixing means for connecting the probe cover to the adapter. The fixing means may be provided in the form of e.g. a clip mechanism and/or any protruding portion. Preferably, the fixing means are adjustable manually in an easy way, in order to facilitate repetitive fixation of disposable probe covers.
According to one embodiment, the adapter is arranged to axially position the probe cover in a first starting position, in which the probe cover can (manually) be coupled to the otoscope, and in a second end position, in which a/the reservoir of the probe cover is displaced relative to the distal end of the head portion. Predefined axial positions, which can be modified, allow for displacing the probe cover about a predefined distance, especially only at a time when the electronic imaging unit is in visual communication with the eardrum. A predefined second axial position allows for determining a specific compressive stress or force or a specific tension, especially tensile stress, which is transferred to the probe cover, especially for homogeneously stretching a reservoir of the probe cover.
According to one embodiment, the adapter exhibits fixing means adapted for engaging an inner lateral surface section of the probe cover. Engaging an inner lateral surface section of the probe cover can ensure reliable or secure connection between the fixing means and the probe cover, even in case relatively high forces have to be exerted on the probe cover. Reliable connection between the fixing means and the probe cover can be ensured even in case the probe cover is provided with very low inherent stability only.
According to one embodiment, the adapter exhibits fixing means adapted for engaging the probe cover along a lateral surface completely in a circumferential direction, especially section by section or along the whole circumference. Thereby, the distal tip or portion of the probe cover can be stretched homogeneously, which may ensure that any line of sight or any of a plurality of radially offset optical axes is not obstructed. Also, relative motion between the probe cover and the head portion may be maximum at any point of the distal tip which is positioned radially offset.
According to one embodiment, the moving mechanism comprises both an adapter which is movably mounted, especially axially movably mounted, and a moving device cooperating with the adapter. The moving device can provide a reaction force, especially in order to determine a threshold value for an axial force which has to be exceeded in order to axially displace the probe cover. This allows for displacing the probe cover only at a time when the distal tip of the head portion is positioned at a transition point or area between soft connective tissue and hard bone confining the ear canal, i.e. at a time when the electronic imaging unit is in visual communication with the eardrum. The moving device preferably defines a first position of the adapter, the first position corresponding to a starting position in which the probe cover and the adapter haven not been moved or displaced yet. The starting position can be defined in conjunction with any mechanical end stop or limit stop which may be provided by the head portion.
According to one embodiment, the adapter is arranged for axially guiding a probe cover along the head portion, especially along a predefined translational axis. This enables a moving mechanism which is not likely to cant or to displace the head portion out of a favorable position within the ear canal.
According to one embodiment, the moving mechanism comprises a moving device which is arranged to exert a reaction force on the adapter, especially in a distal axial direction. This allows for displacing the probe cover only at a specific time, depending on the amount of the reaction force, especially at a time when the electronic imaging unit is in visual communication with the eardrum. Preferably, the moving device is prestressed or elastically preloaded in a direction substantially parallel to the longitudinal axis of the head portion, and the moving device is arranged for positioning the adapter at the mechanical end stop or limit stop.
According to one embodiment, the moving mechanism is arranged to define a threshold value for an axial force exerted on the moving mechanism in the proximal direction. This allows for displacing the probe cover only at a specific time, depending on the amount of the reaction force, especially at a time when the electronic imaging unit is in visual communication with the eardrum. In particular, the threshold value can be defined in dependence on the shape of the head portion. The head portion is shaped such that it can be introduced only as deep as a transition area between soft connective tissue and hard bone. Thus, once the head portion is mechanically blocked within the ear canal, an axial force exerted on the moving mechanism increases, and any latch mechanism of the moving mechanism can be released.
According to one embodiment, the moving mechanism comprises a motion sensor which is connected to the imaging unit and/or to at least one light source and/or to a logic unit of the otoscope, the motion sensor being configured to detect a motion of the moving mechanism and/or of the probe cover relative to the head portion. Such a motion sensor allows for switching on the respective component only at a time when the probability is increased that the electronic imaging unit is in visual communication with the eardrum, i.e. when the electronic imaging unit and the eardrum are arranged on one line of sight.
According to one embodiment, the moving mechanism comprises force detection means. Detecting the force exerted on the probe cover or on the head portion allows for controlling or adjusting an appropriate instant of time for relatively moving the probe cover, especially automatically, such that the use of the otoscope is easy to understand for laypersons. In particular, the layperson does not have to decide whether or when the probe cover has to be moved or unfolded.
When introducing the tip end of the head portion no deeper into the ear canal than to the border between the outer part and the inner part of the outer ear canal of the patient's outer ear, i.e. to a transition area between the two types of tissue, there is the risk that artifacts, such as earwax, hair and other kind of dirt from the outer part of the outer ear canal obstruct the view of the small electronic imaging unit onto the patient's eardrum. Therefore, it is advantageous to take several images from different positions within the ear canal. For doing so, the otoscope according to the present invention may comprise more than one optical axis or cameras at the distal end of its head portion, e.g. two optical axis or cameras, located at different positions on the head portion.
In another preferred embodiment, the otoscope according to the present invention further comprises a motion mechanism configured to allow displacement of the electronic imaging unit or at least one optical axis of the electronic imaging unit relative to the handle portion. With such a motion mechanism, it is possible to position the at least one optical axis in a favorable eccentric observation point, substantially irrespective of the position of the head portion within the ear canal. Also, with such a motion mechanism, it is possible to capture a plurality of images from different positions from one optical axis within the patient's ear canal, thereby avoiding the need for two or more cameras or the need for beam splitter optics. With a motion mechanism, a plurality of favorable eccentric observation points can be realized, although there may be only one single optical axis. If, for example, a hair—at least partially—obstructs the view of the electronic imaging unit at a certain position within the ear canal onto the eardrum, the electronic imaging unit may have a free view onto the eardrum at another position in the ear canal or may at least have a free view onto the part of the eardrum that was partially obstructed by the hair before.
It has been found that positioning the at least one optical axis radially offset induces or brings about that the eccentric observation point positioned at the distal tip on this least one optical axis may be positioned at an unfavorable position, e.g. adjacent to a section of the ear canal having a minimal radius of curvature. Therefore, departing from at least one a radially offset optical axis, the motion mechanism may facilitate to make the concept of “looking around the corner” more practicable.
Moreover, providing such a motion mechanism also allows for automatic identification of different objects in the patient's ear. Usually, in otoscopy, the eardrum represents the object of primary interest. In contrast, artifacts, such as earwax, hair and other kind of dirt, are usually of no particular interest. Such artifacts rather represent a problem when obstructing the view onto the patient's eardrum.
However, since artifacts are relatively close in front of the electronic imaging unit in the ear canal, compared to the eardrum, the artifacts can be distinguished from the eardrum when displacing the electronic imaging unit within the ear canal. That is, artifacts are depicted at distinct positions, if two images are captured from different positions/perspectives within the ear canal (due to their short distance to the electronic imaging unit), whereas the eardrum is shown substantially at the same position (due to the relatively large distance to the electronic imaging unit). According to the principle of stereoscopic viewing, the inventive device enables to determine the distance of different objects with respect to the electronic imaging unit. This determination can be automatically calculated by means of a logic unit, such as a microprocessor, preferably forming part of the otoscope. Furthermore, objects that have been identified as artifacts (due to their close distance to the electronic imaging unit) may be (automatically) eliminated by the image processing unit by comparing two or more images captured from different positions within the patient's ear canal. Consequently, a superimposed image may be generated or calculated by image processing means eliminating the artifacts. The image processing means may be implemented in form of a logic unit, such as a microprocessor provided in the otoscope. Thus, an image clearly depicting the eardrum can be obtained, even if the tip end of the head portion is introduced into the ear canal to the border between the outer part and the inner part of the outer ear canal (and not deeper into the ear canal).
The motion mechanism is preferably configured to allow at least partial rotation of the electronic imaging unit or the at least one optical axis about an axis of rotation. The axis of rotation may correspond to the longitudinal axis of the head portion. By displacing the electronic imaging unit along a predefined motion path, it is possible to automatically calculate the distance of the electronic imaging unit to the detected objects, as described above. In view of the typical size of the artifacts found in the ear canal, such as hair and earwax particles, the motion mechanism preferably allows for displacement of the optical axis of at least 1 mm, more preferable at least 2 mm, further preferred at least 3 mm, within the patient's ear canal. For example, in case a radial offset of 1.8 mm or 2 mm is realized, a rotation of 90° evokes a displacement of about 3 mm. A rotation of at least 90°, more preferably of at least 120°, even more preferably of 180° or even more degrees around the axis may be realized. In conjunction with an electronic imaging unit exhibiting two optical axes or comprising two cameras, a rotation of maximum 90° may be adequate in order to find the most favorable eccentric observation point. In conjunction with an electronic imaging unit exhibiting three optical axes or comprising three cameras, a rotation of maximum 60° or 70° may be adequate. Preferably, the motion mechanism allows for rotation in both directions, i.e. clockwise and counter-clockwise. The motion mechanism may also allow for rotational displacement about more than one axis. The motion mechanism may comprise at least one motor and one or more gears and/or bearings. The electronic imaging unit may be connected to a flexible cable, e.g. a flexible ribbon cable, to allow for such a movement.
Preferably, the probe cover is adapted to be fixed to at least one section of either the head portion and/or the handle portion in such a way that the probe cover does not move relative to the handle portion during displacement of the electronic imaging unit or the at least one optical axis or at least one camera by the motion mechanism. Otherwise, artifacts, such as earwax particles, adhering to the probe cover will be depicted by the electronic imaging unit, even if the electronic imaging unit is displaced by the motion mechanism. This, however, would interfere with object identification and elimination of artifacts from the captured images.
Preferably, the at least one light source is arranged so as to maintain a predetermined distance with respect to the electronic imaging unit or the at least one optical axis, even when the electronic imaging unit or the at least one optical axis is displaced by the motion mechanism. Such a configuration is advantageous, because the predetermined distal relationship between the at least one light source and the optical axis allows for improved (automatic) image analysis. If a motion mechanism is provided, the motion mechanism preferably also displaces the at least one light source. If the light source is provided in the form of a light guide, the light guide should be sufficiently flexible to allow for such a displacement of the at least one light source. Preferably, the light guide is fixed distally within the head portion, wherein the light guide is elastic, the elasticity allowing for bending and/or twisting. Alternatively, the light guide may be rigid, wherein the entire lightning apparatus may be displaced in conjunction with the head portion.
According to one embodiment, the at least one light source is coupled with the motion mechanism, especially directly or via the electronic imaging unit, such that the motion mechanism allows for at least partial rotation of the at least one light source about an axis of rotation, wherein the axis of rotation preferably corresponds to the longitudinal axis. Rotating the light source in a favorable position can allow for observing the entire eardrum with a high reliability.
According to one embodiment, the head portion and/or the handle portion exhibits a form-fit shape which provides a coupling for fixing the probe cover to the otoscope such that it does not move during displacement of the electronic imaging unit or the at least one optical axis or at least one camera by the motion mechanism. The form-fit shape can ensure that artifacts, such as earwax particles, adhering to the probe cover will not be depicted by the electronic imaging unit when the electronic imaging unit is displaced by the motion mechanism. Preferably, the form-fit shape is provided on an outer surface of the head portion or the handle portion.
Preferably, an optical component of the electronic imaging unit or at least one optical axis of the electronic imaging unit or at least one camera is tilted against the axis of rotation so as to be continuously directed to a predetermined point on the axis of rotation, the predetermined point having a fixed distance to the electronic imaging unit or to the camera. In view of the typical length of the inner part of the outer ear canal of the patient's outer ear, the distance may be between 3 mm and 20 mm, preferably between 10 mm and 15 mm. Thus, the “viewing direction” of the electronic imaging unit is optimized for centering on the eardrum, which usually represents the object of primary interest within the patient's ear.
The above mentioned object is achieved according to the present invention by a probe cover adapted to be put over the head portion of an otoscope according to the invention, wherein at a distal end, the probe cover exhibits a reservoir which allows for modifying the shape of the probe cover, especially the shape of a distal end of the probe cover, in order to move the probe cover with respect to the head portion. In particular, the reservoir allows for displacing the probe cover from a first position, in which the probe cover is coupled to the otoscope, to a second position, in which the reservoir is displaced relative to a distal end of the head portion, when a force, especially a pulling force, is exerted on the probe cover. Preferably, at least partially, the reservoir is a folded film or foil portion which can be unfolded when exerting a pulling force on the probe cover. Such a reservoir, especially a folded film or foil reservoir, enables to displace any artifact out of the field of vision of the electronic imaging unit, especially by axially pulling the probe cover in a proximal direction. Alternatively or in addition, the reservoir may be provided by a portion which is more ductile or stretchy or tensile or elastic than other portions or sections of the probe cover, at least partially.
Preferably, the probe cover is designed in a way that allows unfolding or peeling of portions of the probe cover in order to move portions of the probe cover contaminated e.g. with earwax away from the electronic imaging unit. The otoscope preferably contains mechanical means to move the probe cover against the electronic imaging unit or vice versa.
According to one embodiment, the reservoir is provided by a portion of the probe cover which is arranged centrally at a distal tip of the probe cover, or by a portion of the probe cover which annularly overlaps an outer section of a distal tip of the probe cover, or by a plurality of concentric circular bends provided at a distal tip of the probe cover. Each of these embodiments provides an arrangement which can ensure that any artifacts can be effectively displaced out (radially) away from an observation point at the distal tip of the head portion, especially a favorable eccentric observation point. In particular, annularly overlapping sections and/or a plurality of concentric circular bends provided at a distal tip provides the advantage that there is no need for a groove, recess or cavity at the distal tip of the head portion for accommodating the reservoir. Rather, a further sensor, e.g. an infrared sensor unit, may be arranged directly at the distal tip, especially centrically.
A distal tip of the probe cover may be conceived as a front face or front side of the probe cover.
According to one embodiment, at a proximal end, the probe cover exhibits a protrusion which is arranged for axially position the probe cover with respect to the head portion. A predefined axial position, which can be modified, enables to displace the probe cover only at a time when the electronic imaging unit is in visual communication with the eardrum.
According to one embodiment, the probe cover is a double-ply probe cover. A double-ply probe cover provides high structural stability, even if the probe cover is made by deep-drawing. Preferably, the distal foil portion covering the camera is very thin and transparent, exhibiting a wall thickness of e.g. 30 micrometer (μm) to 50 micrometer, especially 20 micrometer.
According to one embodiment, the reservoir is provided by an inner shell of the double-ply probe cover. This design can ensure that the reservoir can be covered by an outer shell of the probe cover, at least partially. Thus, any artifacts can be kept away from the inner shell more effectively. Also, any contact of the reservoir with an inner lateral surface of the ear canal can be avoided or prevented, preventing premature unfolding of the reservoir.
According to one embodiment, the probe cover is a double-ply probe cover, wherein at least one gap or groove between shells of the probe cover provides a gas conduit, especially an air channel into the ear canal during examination. This allows for pressurizing the eardrum.
According to one embodiment, the probe cover exhibits two shells which both provide a form-fit protrusion, especially a U-shaped rim, adapted for interlocking with the probe cover moving mechanism, wherein the protrusions lie on top of each other. Alternatively or in addition, the probe cover may exhibit two shells which are bound together at the proximal end by welding, e.g. ultrasonic welding, or by gluing. Such a design can ensure that both shells are displaceable by a moving mechanism, preventing that one of the shells is displaced relative to the other, which eventually could cause twisting or distortion of the probe cover.
According to one embodiment, at a distal tip, the probe cover exhibits an opening and/or a predetermined breaking or unfolding point. Such a design enables displacement of the respective section of the probe cover, especially of an outer shell of the probe cover, out of the field of vision, especially at a time when the electronic imaging unit is in visual communication with the eardrum.
According to one embodiment, the probe cover is a molded plastic, especially made by deep-drawing or thermoforming, wherein the material of the probe cover preferably is polypropylene. Such a probe cover can easily be provided as a disposable, especially in a cost-effective way. Thus, laypersons do not have to clean or sterilize any component of the otoscope. Also, such a probe cover can exhibit an adequate stiffness, in order to prevent twisting or any distortion of the probe cover during insertion of the head portion into the ear canal. Also, such a probe cover can exhibit an adequate stiffness allowing for transferring an axial reaction force to the moving mechanism, in order to initiate displacement of the probe cover only when a specific threshold value of a force exerted on the probe cover or head portion is exceeded. In other words: The material or the stiffness is provided such that displacing the probe cover can be initiated automatically based on mechanical reaction forces, and does not occur prematurely during insertion of the otoscope into the ear canal.
According to one embodiment, in a distal direction, the probe cover exhibits a decreasing wall thickness towards the distal end, especially decreasing at least by half, or decreasing by 1/10 to 1/20. On the one hand, such a taper can ensure adequate stiffness of a proximal portion of the probe cover, especially of a portion which is provided for transferring axial forces to the otoscope. On the other hand, a relatively low wall thickness at the distal tip can facilitate unfolding. The wall thickness or the tapering preferably is in the range between 10 micrometer and 100 micrometer, further preferred between 5 micrometer and 70 micrometer, especially between 20 micrometer and 50 micrometer.
According to one embodiment, the probe cover is adapted to be fixed to at least one portion of the head portion and/or the handle portion of the otoscope in such a way that the probe cover does not move relative to the handle portion during rotation of the electronic imaging unit or the at least one optical axis.
According to one embodiment, at a proximal end, the probe cover exhibits a collar, especially a radially protruding discoid collar, which is arranged for fixing the probe cover at a stationary portion of the head portion and/or at the handle portion. A collar can ensure exact positioning of the probe cover with respect to the handle portion or the head portion. The collar may also provide a stiff handle area to manually mount the probe cover on the otoscope. Also, the collar can protect the handle portion from any body fluids. Thus, laypersons do not have to clean or sterilize any component of the otoscope.
According to one embodiment, the otoscope further comprises an infrared sensor unit positioned at the distal end of the head portion, especially at a distal tip of the head portion, especially centrically. The infrared sensor unit may be provided as a component of the electronic imaging unit, or as a separate sensor unit. Providing an otoscope comprising an infrared sensor unit for temperature detection in conjunction with an optical identification of objects allows for more reliable identification of the objects, e.g. of the eardrum. Providing an otoscope additionally with an infrared sensor unit allows for minimizing any risk of misdiagnosis. Pre-diagnosis may be facilitated. Temperature detection may assist a physician in carrying out diagnosis. Any more advanced or final disease diagnosis has to be carried out by the physician on the basis of other symptoms exhibited by the subject, which are observed by the physician, or by the physician's further examination.
The infrared sensor unit may be connected to a logic unit, the logic unit being configured for processing data from both the infrared sensor unit and the electronic imaging unit, especially simultaneously. Data acquired by the infrared sensor unit can be verified based on data acquired by the electronic imaging unit, and vice versa. The infrared sensor unit can be provided at same positions like positions discussed in context with the electronic imaging unit or the light sources. Likewise, the infrared sensor unit can be displaced in the same manner as discussed in context with the electronic imaging unit or the light sources.
The otoscope may further comprise a logic unit, such as a microprocessor. The logic unit may be configured to control the electronic imaging unit and/or the at least one light source and/or an infrared sensor unit. The logic unit may analyze the images obtained by the electronic imaging unit e.g. in order to detect an inflammation of the eardrum and/or the inner part of the outer ear canal, and/or in order to compare two images obtained with the electronic imaging unit located at different positions within the ear and/or with the object illuminated from different positions, so as to identify and discriminate different objects in the patient's ear. The logic unit may further be configured to generate or calculate a new image wherein predetermined objects that have been previously identified are eliminated.
The above mentioned object is achieved according to the present invention by an ear inspection device, comprising an otoscope according to any one of the embodiments of the present invention, further comprising a probe cover according to any one of the embodiments of the present invention. For example, the ear inspection device can be provided as a kit or assembly, including e.g. a plurality of disposable probe covers, or the ear inspection device can be provided with the probe cover mounted at or fitted onto the head portion.
According to one particular embodiment, the above mentioned object is achieved according to the present invention by a method of identifying objects in a subject's ear, wherein the method comprises the following steps:                introducing a head portion of an otoscope in conjunction with an at least partially transparent probe cover put over the head portion into an ear canal of a subject's outer ear, the head portion accommodating an optical electronic imaging unit which exhibits at least one optical axis;        moving at least a portion of the probe cover with respect to the at least one optical axis, especially automatically, e.g. by a motor or by a mechanical latch mechanism or against an axial force of an elastic element; and        using the electronic imaging unit to capture at least one image.        
The step of relatively moving at least a portion of the probe cover may be initiated, especially automatically initiated, in dependence on a force exerted on the probe cover or the head portion, wherein the force may be detected by a force sensor accommodated within the head portion or the handle portion of the otoscope. Alternatively, the step of relatively moving at least a portion of the probe cover may be initiated mechanically, especially by a pretensioned or preloaded compression spring which is compressed only when the (axial) force exerted on the probe cover or the head portion exceeds a threshold value.
The step of relatively moving at least a portion of the probe cover may comprise axially displacing a proximal end of the probe cover with respect to the head portions and radially displacing a distal tip of the probe cover with respect to the distal tip or front side of the head portion. This may effectively displace ear wax or any other object adhering the probe cover.
The method may further comprise the step of using the electronic imaging unit to capture a plurality of images from an observation point arranged on the at least one optical axis, especially from a plurality of different eccentric observation points.
According to one particular embodiment, the above mentioned object is achieved according to the present invention by a method of identifying and medically characterizing the eardrum in a subject's ear, characterized in that the method comprises the following steps:                introducing a head portion of an otoscope in conjunction with an at least partially transparent probe cover, which is put over the head portion, into an ear canal of a subject's outer ear, the head portion accommodating an optical electronic imaging unit which exhibits at least one optical axis;        detecting a force exerted on the head portion or the probe cover during introduction, especially a force in a direction substantially parallel to a longitudinal axis of the head portion; and        moving at least a portion of the probe cover with respect to the at least one optical axis, especially in dependence on a specific threshold value of a detected force;        using the electronic imaging unit (40) to capture at least one image of the eardrum; and        evaluating a medical condition of the eardrum by medically characterizing the eardrum based on at least one image captured of the eardrum, in order to provide medical evidence of the eardrum.        
Medically characterizing the eardrum preferably is carried out automatically by the device, especially based on predefined ranges, e.g. with respect to temperature or a specific degree of reddishness. In other words: Medically characterizing the eardrum comprises at least one step of automatically evaluating the imaged captured by the electronic imaging unit, especially by means of a logic unit, e.g. based on one of the characteristics of the eardrum described above.
Such a method may provide a layperson with a diagnosis, especially a pre-diagnosis, substantially irrespective of any skills of the layperson, in particular substantially irrespective of the position of the head portion within the ear canal. In other words: the otoscope is configured for reliably providing the layperson with medical information, e.g. in order to facilitate any decision whether a physician should be visited. Thereby, capturing images in dependence on a specific force enables evaluation of images which show the eardrum with high reliability. Misdiagnosis may be precluded more effectively, even when the method or the otoscope is applied by laypersons.
The method may comprises the step of using an infrared sensor unit for detecting the temperature of the objects, the infrared sensor unit preferably being positioned at a distal end of the head portion. Detecting the eardrum's temperature may facilitate diagnosis and may further facilitate to provide a layperson with medical information, without the need of visiting a physician.
In case any reference sign is not explicitly described in a respective figure, it is referred to the other figures. In other words: Like reference characters refer to the same parts or the same type or group of device throughout the different views.